Gradient Four-Vector
The 4-dimensional version of the Gradient, encountered frequently in general relativity 
and special relativity, is
which can be written
where
is the d'Alembertian Operator.See also d'Alembertian Operator, Gradient, Tensor, Vector
References
Morse, P. M. and Feshbach, H. ``The Differential Operator 
.'' §1.4 in Methods of Theoretical Physics, Part I. New York: McGraw-Hill, pp. 31-44, 1953.
- Multiplication Table
- Multiplicative Character
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- Multiplicative Function
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- Multiplicity
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- Multisection
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- Multivariate Analysis
- Multivariate Function
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- Mu Molecule
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